Photovoltaic and solar thermal co-generation storage wall module and heat-pump system

ABSTRACT

A wall module used to retrofit any existing building into solar building or construct new solar building is made of a hybrid photovoltaic and solar thermal plate, a heat pipe, a solid thermal energy storage, a glass cover, and a heat-pump system. When the incident sunlight penetrating through the transparent glass cover reaches to the cogeneration plate, portion of it is converted into electricity and the rest becomes into heat; then the heat is transferred back to the solid thermal storage; when it is needed for heating and cooling, the stored heat is retrieved and transported to its destination with heat pump system; during the transportation process, the temperature of the stored heat is boosted up. Any buildings, no matter existing building or new building, can be converted into a large scale solar power generation and storage station using the wall modules of present invention without changing their structures and functions. As the buildings share the insulation with the wall modules, the addition of the wall modules will significantly improve the encapsulation of the buildings. The wall modules change the whole body of building into large scale storage without occupying the interior space of the building.

TECHNICAL FIELD

The present disclosure relates generally to solar collection, solar power generation and solar energy storage systems, more specifically, to photovoltaic and solar thermal cogeneration wall module with thermal storage and heat-pump heat transfer system.

BACKGROUND

The Sun provides Earth with as much energy every hour as human civilization uses every year (O. Morton, 2006, “Silicon Valley Sunrise”, Nature, 443, Sep. 7, 2006). If a small fraction of those sun rays were captured and used in place of fossil fuels, there would be no need for power plants with environmentally disastrous greenhouse gas emissions. Buildings occupy a large portion of the earth's land and therefore have the potential to be large scale solar collectors. However, rather than contributing to the energy collection efforts, buildings consume huge amounts of energy due to solar radiation. In the United States, heating and cooling buildings is responsible for 38% of carbon dioxide emissions, 71% of electricity consumption, 39% of energy use, and 12% of water consumption. Efficient solar energy use in buildings will significantly impact the entire landscape of energy consumption and carbon dioxide emission. Currently, the green building movement is focused on increasing the efficiency of existing technologies, which is slowly progressing the efficiency and affordability of these technologies for homeowners.

There is another approach in changing the encapsulation structure of the building walls, to serve as an integrated solar collection and storage module. The solar collector consists of a hybrid photovoltaic and solar thermal flat plate panel that improves both the photovoltaic conversion efficiency and the total conversion efficiency. Heat generated from the hybrid panel will be stored within the walls of the body of the building and an active circulation system will extract the stored heat for distribution and various applications.

A concentrating solar thermal system will be installed on the roof of the building to boost the temperature of the stored heat to foster the thermal power generation system through the Green Turbine. In conjunction with a thermal heat pump, the system will heat the building in winter, cool the building in the summer, and generate power throughout the autumn and spring. Further, the insulation materials used with the thermal storage also improves the building envelope. The synergetic combination of the photovoltaic system, thermal storage, and the thermal power generation system will enable the alternative power generation from PV to power a thermal engine. Effectively, this will stabilize the power generation of the building making the building into a large-scale solar collector and stabilized distributed power plant, without altering the structure of function of the building.

Current solar building technology can be separated into several categories: power generation, heat generation, solar thermal, and power cogeneration systems. In the power generation category, extra PV arrays are simply added to a building to generate electric power. Although PV shingles and other building block PV panels are commonly adopted to build new buildings or retrofit existing buildings, the majority of PV systems are added components to buildings. The heat generation category could be classified into two subcategories, one is active building and the other is passive building. An active building operates through added solar collection systems in which energy conversion and transportation are actively controlled. A passive building operates through specially designed building structure and intensively selected materials called thermal mass, and energy collection/transportation is not controlled. In solar thermal and power cogeneration optimized buildings, combined PV and solar thermal (PVT) panels are adopted to enhance electric power generation and raise the total conversion efficiency of the systems. In these systems, although the total conversion efficiency is improved dramatically, the yield power output of the system is mostly low-grade heat. In the summer, spring and autumn, the surplus heat supply is not utilized. The current state of solar building technology has some drawbacks:

Solar collection, conversion and storage system are not parts of building structure

Building structure has to be manipulated to harvest and store solar energy

Heat transfer and distribution is not actively controlled

Majority of heat harvested from solar radiation is not converted into electric power

The output electric power is intermittent

Building envelope is not improved by the added solar systems

Building system does not work at maximum output capacity during entire year

The present invention is to provide a core component of solar building photovoltaic and solar thermal cogeneration wall module with thermal storage and heat-pump heat transfer system to convert any type of building into a solar building without changing its structure and function. The wall modules are comprised of hybrid photovoltaic and solar thermal collectors, one-direction passive heat transfer devices, thermal storage, and heat-pump active heat transfer system. The collectors are hybrid PV and thermal panels, and the storage incorporate heat exchangers for the heat-pump system to retrieve the stored heat, boost the temperature and redistribute it to the building and electric power conversion systems. The Green Turbine could be incorporated into the building to convert the stored heat into electric power, and a solar concentrating system is added to boost the temperature of the heat stored in wall modules for improving efficiency of the thermal power generation systems. The PV system and the thermal power generation systems will alternate to mitigate the intermittence of the building power through smart control systems.

Like building blocks, the wall modules serve as energy collection/storage equipment and as part of the building's structure. The adoption of the hybrid PV and thermal panel as the solar collector for our wall modules will raise the electric conversion efficiency from 15-20% to about 72%. The addition of wall modules to a building will dramatically improve the envelope of the building through the shared thermal insulation of the solar collection system and the building structure. The heat transfer and transportation of the harvesting process and distribution process are controlled by a forced circulation and distribution system. Stored low grade heat is boosted to high temperature by employing solar concentrating systems and then converted into electricity through the Green Turbine thermal power generation system. The system's electrical power output is balanced through alternation of PV power generation and thermal power generation without the addition of batteries or other electric storage systems.

The present invention provides an approach to convert any type of building into a high-efficiency large-scale solar collector and storage building without changing its structure or function. This will offer enhanced energy generation beyond conventional PV, and foster energy savings through an improved building envelope. The building will become a distributed power generation station with stabilized power output. It has the potential to turn an urban area into a stabilized power plant for the utility power grid. The proposed technology maximizes power output throughout the four seasons. It optimizes the energy supply for thermal applications and power applications in order to improve the utilization efficiency.

The overall goal of the present invention is to provide a building block that cogenerates electricity and thermal energy and stores the generated thermal energy into the block via passive circulation process, then the stored thermal energy is retrieved and boosted to high temperature and redistributed to wherever it needed via an active heat-pump system, consequently provide a design paradigm of solar buildings and develop the corresponding solar energy collection and conversion equipment to realize ultra-high total energy conversion efficiency. This goal results in: distributed energy storage throughout the building body, system function alternation between the heating, cooling and PV/thermal power generation systems, substantial improvement of the building envelope, and ultra-high total electric power conversion efficiency.

SUMMARY

According to the present invention, a photovoltaic and solar thermal cogeneration wall module with thermal storage and heat-pump heat transfer system is provided to dramatically increase the total conversion efficiency of solar system, store the harvested thermal energy in the building body, avoid the reverse heat transfer from the storage of the building during night, and boost the stored energy to high temperature during the heat transfer to utilization sites. The embodiment of the invention is a building block constructed with a hybrid photovoltaic and solar thermal flat plate, a thermal storage, one-direction heat transfer heat pipes, and heat-pump heat transfer system. The building block is assembled by welding the one-direction heat transfer heat pipes on the hybrid photovoltaic and solar thermal flat plate, connecting the hybrid plate with the storage by inserting the heat emitting ends of the heat pipes into the storage either solid storage or liquid storage, arranging the heat exchange coils of the heat-pump heat transfer system into the storage, and insulating the storage on the both sides opposite to the hybrid plate and the interior of building. When the incident sun light is absorbed by the hybrid plate, portion of the input light is directly converted into electricity and portion of the light is converted into heat, the heat is transferred into the storage by the heat pipes, due to the one-direction heat transfer feature, the reverse heat transfer during night is stopped, the stored heat is retrieved and boosted to high temperature when it is needed by the heat-pump heat transfer system.

Further aspects and advantages of the present invention will become apparent upon consideration of the following description thereof, reference being made of the following drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several embodiments of the invention and together with the description, serve to explain the principles of the invention.

FIG. 1 is the cross section of the photovoltaic and solar thermal cogeneration wall module with thermal storage and heat-pump heat transfer system, which shows the composition of the system and the structure of the apparatus.

FIG. 2 shows the connection of the wall module and the heat-pump system, where the heat-pump system transfers the stored heat to wherever it is needed and boosts the temperature to high level in the mean while.

FIG. 3 is the core component of the wall module photovoltaic and solar thermal cogeneration plate and the heat pipe for one direction heat transfer to the back thermal storage, where the solar cells are laminated on a metal plate and a heat pipe is welded on the backside of the plate.

FIG. 4 is the backside view of the assembly of the heat pipe array and the front insulation plate of the back thermal storage.

FIG. 5 is the overview of the wall module package.

FIG. 6 shows the heat exchanger of the heat-pump system buried in side of the back thermal storage.

FIG. 7 is the core component photovoltaic and thermal cogeneration vacuum pipe with heat pipe for the second embodiment of the present invention.

FIG. 8 is the cross section of the wall module of the second embodiment showing the composition and structure of the apparatus.

FIG. 9 is the overview of the wall module of the second embodiment.

FIG. 10 is the cross section of the wall module of the third embodiment showing the composition and structure of the apparatus.

FIG. 11 is the overview of the wall module of the third embodiment.

DETAILED DESCRIPTION

Reference will now be made in detail to the present exemplary embodiments, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

Referring to FIG. 1, the first embodiment of the wall module of the present invention is consists of components, cogeneration plate 10, which is constructed by laminating solar cells on metal plate, heat pipe 20, which is welded on the backside of the metal plate, the front insulation of the back thermal storage 30, which isolates the cogeneration plate 10, and the solid thermal storage media 55, which is filled in the storage space, the back insulation of the back thermal storage 40, the circulation coil of the heat-pump system 50, which is buried into the solid thermal storage media 55, and the glass cover 60. When the wall module is in operating, the incident sunlight penetrating the glass cover reaches to the cogeneration plate 10, portion of it is converted into electricity and rest part becomes into heat, the heat is collected and transferred back into the storage media 55 by the heat pipe 20. When needed, the stored heat will be retrieved and transferred by the heat pump system through the circulation coil 55 to wherever it is needed, and during the transfer process the temperature of the stored heat is boosted up based on usage.

Referring to FIG. 2, the heat-pump system 70 is connected with the wall module and retrieves the stored heat to boost to high temperature and transfer to destinations of utilizations.

Referring to FIG. 3, the heat pipe 20 is welded on the backside of the cogeneration plate 10.

Referring to FIG. 4, the heat pipes 20 are assembled into an array and penetrate through the front insulation 30 into the back thermal storage.

FIG. 5 shows the overview of the packed wall module.

Referring to FIG. 6, the circulation coil 50 of the heat pump system is installed into the back storage filled with solid thermal storage media.

Referring to FIG. 7, in the second embodiment of the present invention, the cogeneration plate 90 and the heat pipe 80 are encapsulated into a vacuum pipe.

Referring to FIG. 8, the heat pip 80 penetrates through the front insulation into the back thermal storage. The heat generated in the vacuum pipe is transferred into the thermal storage via the heat pipe, and the heat transfer is one-direction, it only happen in the day time, no reverse heat transfer in night time.

FIG. 9 shows the overview of the packed wall module of the second embodiment of the invention.

Referring to the FIG. 10, in the third embodiment of the present invention, the circulation coil 120 of the heat pump system is directly welded on the cogeneration plate 110, the back storage space 130 is filled with solid thermal storage media, the glass cover 140 forms an air space in the front of the cogeneration plate. During the daytime, the heat generated on cogeneration plate is transferred into the thermal storage media and during the night time, the stored heat is retrieved by the heat-pump system via the circulation coil welded on the cogeneration plate.

FIG. 11 shows the overview of the wall module of the third embodiment of the present invention.

From the description above, a number of advantages of the wall module become evident. The wall module not only generates both electrical energy and thermal energy to dramatically increase the total conversion efficiency of solar system, but also stores the generated thermal energy, this enables the whole building built with the wall modules to be a large scale power generation and storage system. The storage of the wall modules not only make the building body into a large scale energy storage, but also significantly improve the encapsulation of the building as the building shares the two layers of the insulation of the storage with the wall modules. The wall module, in conjunction with the heat-pump system, separate the thermal energy collection and utilization processes, the collection process is a natural process, while the utilization process is an active process. Relative to the passive solar building, the heat collection and utilization are totally under control in the building built with the wall modules of the present invention. 

I claim:
 1. An assembly is consists of a cogeneration plate, which is a metal plate laminated with solar cells, solid thermal energy storage media, heat pipe, circulation coils of heat-pump system, insulation layers and glass cover, where the heat pipe is welded on the metal plate of the cogeneration plate, the glass cover is installed in front of the cogeneration plate leaving a air space, the cogeneration plate is isolated with the thermal energy storage media by the front insulation layer of the storage, and the heat pipe penetrates through the front insulation layer into the storage, the storage is isolated with the outside by the back insulation layer of the storage, the circulation coil of the heat pump system is inserted into the thermal storage media and connected to the heat-pump system; wherein the incident sunlight penetrating through the glass cover and reaching to the cogeneration plate will be partially converted into electricity by the solar cells laminated on the metal plate and rest of it will be converted into heat and collected by the metal plate, then transferred into the thermal storage by the heat pipe welded on the metal plate, when needed, the stored heat will be retrieved by the heat pump system via the circulation coil, mean while, the temperature of the stored heat will be also boosted up.
 2. The cogeneration plate and heat pipe combination of claim 1 could be encapsulated into a vacuum pipe and have the heat pipe penetrate through the front insulation into the storage of the claim 1 to avoid glass cover of the claim
 1. 3. The circulation coil of heat pump system of the claim 1 could be directly welded on the metal plate of the cogeneration plate of the claim 1 to avoid the heat pipe and the cogeneration plate could directly touch to the thermal storage media of the claim 1 to avoid the front insulation of the thermal storage of the claim
 1. 